Understanding Soft Focus and Sharp fall-off

[ewood]

I just purchased a Calumet 8x10 camera and now I need to buy a lens. I'm new to film and new to large format so I'm reading as much as I can and filling in the gaps with posts to this forum.

I would like to do close up portraits (waist level and up) and I want a very sharp focus with very short depth of field and a sharp fall-off. Now, by this I mean that I would like to compose and setup a shot (indoors...in my home since I'm a hobbyist still) where I can have the subjects eyes in very sharp focus and have the hair, ears, neckline, etc quite noticeably out of focus.

I'm trying to select the right lens for this application (tight spaces, portrait lens, wide aperature on an 8x10). And obviously I would need a lens board so if I find a Copal #3 lens that suits my needs and budget then can I just buy any Copal #3 lens board and it will work with my camera? I'm still trying to navigate all of this. I'm doing more reading tonight.

Thanks in advance for anyone willling to help.
Cheers,
Eric

[eddie]

most very short DOF lenses (f3) will not fit on the 6x6 lens board AND cover 8x10. do you have a reducing back to 5x7? if so you can easily get what you want.

if not keep an eye out for the many f4.5 lenses that will cover 8x10. they include heliar. a 360 would be perfect. there are others too. the various tessar lenses will work as well. many are f4.5

none of the above are "soft focus" but they will give you sharp centers with excellent fall off.

eddie

[Jon Shiu]

You have to buy a lens board that fits your specific model of camera. For example Calumet 8x10 can mean a C-1, or it can mean a Calumet Cambo type, which takes a different type of lens board.

Assuming you have a Cambo type, you would want either a Calumet (or Cambo) 8x10, board with two notches at the top.

Jon

[Gem Singer]

Check out KEH (www.keh.com) for a large selection of previously owned lenses and lens boards.

Look for a lens with a focal length of 300-360mm. Any lens of that focal length, from one of the "big four" lens manufacturers, will do what you describe for portraiture.

Just be sure that you match up the proper lens board for your particular camera.

Lens boards that are milled for Copal 3 shutters are listed on the KEH website as having 65mm openings.

[Jay DeFehr]

Eric,

I don't think you want a SF lens. To get very shallow dof you'd have to use a wide aperture, and then you can forget about anything being in "very sharp focus" with a SF lens. I'd heed the excellent advice given by all above.

[ewood]

Thanks for all the feedback, it has definitely helped me to understand more about what I need. I will look for a 300 - 360mm lens f/4.5 which is paired with a cambo lens board. If it's not paired then I need to by a cambo lens board with the same Copal value as the lense? And KEH, B&H are good sites to start my search?

[ewood]

Ok, so I've found the following lens (couldn't find one on KEH or B&H with a f/4.5). However, I can't tell what lens board to buy because the lens information doesn't list the Copal value. Is there another way to figure this out? I appreciate you teaching a man to fish.

http://www.ebay.com/itm/VINTAGE-GERM...88771155056368

Cheers, Eric

[Kimberly Anderson]

Canham 8x10 w/5x7 reducing back. Schneider G-claron 355, wide-open (f/9). About 10 feet away.



The DOF is literally only the bridge of his glasses.

[Jon Shiu]

Ok, so I've found the following lens (couldn't find one on KEH or B&H with a f/4.5). However, I can't tell what lens board to buy because the lens information doesn't list the Copal value. Is there another way to figure this out? I appreciate you teaching a man to fish.

http://www.ebay.com/itm/VINTAGE-GERM...88771155056368

Cheers, Eric

That's a lens in barrel, ie doesn't have a shutter. You need to buy a lens in shutter. A 300mm f5.6 lens also has shallow focus wide open.

Jon

[tgtaylor]

Ok, so I've found the following lens (couldn't find one on KEH or B&H with a f/4.5). However, I can't tell what lens board to buy because the lens information doesn't list the Copal value. Is there another way to figure this out? I appreciate you teaching a man to fish.

http://www.ebay.com/itm/VINTAGE-GERM...88771155056368

Cheers, Eric

Ewood,

That lens doesn't have a shutter. To use it as it is, you will have to stop the exposure with the cap or a hat. Otherwise you will have to buy a shutter to mount it in.

Thomas